The present invention relates generally to electrical switches, and more particularly, to a rocker switch having a molded cylindrical seal mounted on an upwardly cylindrical barrel located in an upper compartment of a switch housing.
Sealing electrical switches from moisture penetration is well known in the art. For example, in a switch having a switch housing and a cover, it is known to interpose a seal member across the entire peripheral mating surfaces of the housing and the cover. The prior art also suggests that it is effective, particularly for electrical switches, to mold the seal member directly to an outer peripheral mating surface of the switch housing for secure and precise positioning thereof. Such additional molding could be accomplished by injection molding, which utilizes separate molding dies to hold the switch housing therebetween and injects an elastic material to form the seal member around the top periphery of the switch housing. In this design, however, there remains a problem that, when separating the molding dies after injection-molding of the seal member, the seal member may be pulled in opposite directions as the dies are removed, which may separate the seal from the switch housing, thereby defeating the purpose of this injection molding technique.
Attempts have been made to overcome the above problem by providing a seal for an actuator opening in a switch housing wherein the seal is separately mounted between peripheries of the switch housing and the cover. One such seal for electrical switches that has a non-removable rocker button includes a one-piece diaphragm seal that covers the entire top end of the switch housing to seal the interior of the switch base from the outside. The diaphragm seal is placed across the entire open end of the frame, and two depending posts of a rocker button extend through the seal. This particular construction relies on uniform engagement of the face edges of the base and the frame to properly maintain the seal in position. However, the constant movements of the rocker button stresses the seal near the center, which can pull away if the two faces are not uniformly clamped, thus allowing moisture into the switch.
Another switch sealing arrangement includes placing an O-rings seal into a tower. The O-rings is inserted blindly from the bottom of the frame and held in place by the switch actuator, which is also inserted from the bottom of the frame into pivots. The switch actuator and seal are retained in the pivoted location by attachment of the switch base and movable contacts. The post of the rocker button is inserted into a hole in the actuator. However, this arrangement is difficult and time consuming to assemble.
In view of the aforementioned problems, it would therefore be desirable to design an improved switch and seal arrangement that effectively seals the switch interior without placing undue stress on the sealing arrangement due to prolonged switch use, and that is also easy to assemble.
The present invention provides a switch and sealing arrangement that 1) improves sealing capability of the rocker switch, 2) provides an arrangement that minimizes distortion or stress to the seal, 3) allows easy assembly of the switch and seal, 4) permits for a removable rocker button, and 5) provides a plurality of apertures to allow fluid drainage from the switch and therefore, overcomes the shortcomings of the prior art.
Accordingly, the present invention includes a switch housing having an upper compartment, a lower compartment, and an inner base. The upper compartment is in communication with an exterior of the switch housing, and the lower compartment is defined by a plurality of walls extending from the upper compartment to receive an electrical contact assembly therein. The inner base extends across the switch housing and separates the lower compartment from the upper compartment and has a cylindrical barrel extending upwardly therefrom. The invention also includes a seal and a rocker button mounted on the upper compartment of the switch housing. The seal has an outer lip and an inner opening and is mounted on the upwardly extending cylindrical barrel. The outer lip of the seal is fitted on an outer surface of the cylindrical barrel. The rocker button is positioned in the upper compartment of the switch housing and is engageable thereto. The rocker button has a post extending downwardly therefrom that is insert into the inner opening of the seal to thereby seal the lower compartment from the upper compartment.
In accordance with another aspect of the invention, a switch housing has an upper compartment that is in communication with the exterior of the switch housing, an inner base, a cylindrical barrel extending upwardly from the inner base, and a plurality of apertures open into the atmosphere to allow drainage from the upper compartment. The cylindrical barrel defines an upper end of a switch cavity. The switch housing also includes a seal and a rocker button mounted on the upper compartment of the switch housing. The seal has an outer lip and an inner opening and is mounted on the upwardly extending cylindrical barrel such that the outer lip is fitted on an outer surface of the cylindrical barrel. A rocker button is engageable with the switch housing and has a post centrally located and extending downwardly from the rocker button. When assembled, the post is inserted into the inner opening of the seal to thereby seal the switch housing from the exterior. The switch housing further includes a pair of lugs molded on opposite sides of the upper compartment to snap fit the rocker button to the switch housing. The rocker button also includes a pair of prongs on opposite sides of the rocker button to snap fit with the pair of the lugs.
Various other feather, objects and advantages of the present invention will be made apparent from the following detailed description and the drawings.